CN112639716B

CN112639716B - Reader-writer, control method of reader-writer, and storage medium

Info

Publication number: CN112639716B
Application number: CN201980057264.1A
Authority: CN
Inventors: 肥塚八寻
Original assignee: Omron Corp
Current assignee: Omron Corp
Priority date: 2018-10-30
Filing date: 2019-09-18
Publication date: 2024-01-19
Anticipated expiration: 2039-09-18
Also published as: WO2020090269A1; JP2020071612A; JP7155879B2; DE112019005456T5; CN112639716A

Abstract

The invention provides a reader/writer, a control method of the reader/writer, and a storage medium, which can suppress an increase in cost and increase the capacity of information that can be managed by an RF tag. The reader/writer includes: an RF tag specifying unit (21) that specifies a predetermined plurality of RF tags (40) as target RF tags (40); and a memory processing unit (22) that performs memory processing for reading and writing in at least one virtual memory space by integrating memories included in each of the plurality of target RF tags (40).

Description

Reader-writer, control method of reader-writer, and storage medium

Technical Field

The present invention relates to a reader/writer (reader writer) that reads and writes data from and to a Radio Frequency (RF) tag, a method of controlling the reader/writer, and a storage medium.

Background

Conventionally, in order to perform individual management at a manufacturing site or a logistics site, the following readers are known: data is read from or written to an RF tag attached to an individual, and data is exchanged with an industrial control device such as a programmable logic controller (Programmable Logic Controller, hereinafter simply referred to as "PLC").

In these readers/writers, communication with an RF tag is generally performed via wireless communication, and in order to improve reliability of wireless communication, there is a technique of performing anomaly detection by adding a cyclic redundancy code (Cyclic Redundancy Code, CRC) to data from the RF tag (for example, refer to patent document 1).

Prior art literature

Patent literature

Patent document 1: japanese patent publication No. 3007926, 12 nd, 3 rd registration 1999 "

Disclosure of Invention

Problems to be solved by the invention

In recent years, however, the volume of information used for individual management at a production site has increased. However, the memory capacity of the RF tag, which is a general product, is small, and there is a problem that the memory capacity of the RF tag is insufficient with respect to the necessary data capacity. On the other hand, the RF tag having a large memory capacity has a problem of high unit price, increased cost, and the like.

An embodiment of the present invention aims to implement the following techniques: the cost can be suppressed from increasing, and the capacity of information that can be managed by the RF tag can be increased.

Technical means for solving the problems

In order to solve the above-described problem, a reader/writer according to an embodiment of the present invention performs at least one of reading and writing of data by wireless communication with an RF tag, and includes: an RF tag specifying unit that specifies a predetermined plurality of RF tags as target RF tags; and a memory processing unit that integrates memories included in each of the plurality of target RF tags, and performs memory processing of at least one of reading and writing as one virtual memory space.

Further, in order to solve the problems, a control method of a reader/writer according to an embodiment of the present invention includes the steps of: determining a predetermined plurality of RF tags as target RF tags; and integrating memories included in each of the plurality of target RF tags, and performing memory processing of at least one of reading and writing as one virtual memory space.

In order to solve the above-described problems, a storage medium according to an embodiment of the present invention stores a program for causing the reader/writer to operate, and causes a computer to function as the RF tag determination unit and the memory processing unit.

ADVANTAGEOUS EFFECTS OF INVENTION

According to an embodiment of the present invention, an increase in cost can be suppressed, and the capacity of information that can be managed by an RF tag can be increased.

Drawings

Fig. 1 is a block diagram showing the essential structure of a reader/writer according to an embodiment.

Fig. 2 is a diagram schematically showing a system environment in which a reader/writer is used.

Fig. 3 (a) and 3 (b) are block diagrams showing the configuration of a system using a reader/writer.

Fig. 4 is a diagram showing an example of the flow of data between the reader/writer and the RF tag.

Fig. 5 is a flowchart showing a specific example 1 of the flow of the read processing of the reader/writer.

Fig. 6 is a flowchart showing a specific example 2 of the flow of the read processing of the reader/writer.

Fig. 7 is a diagram showing an example of the flow of data among the PLC, reader/writer, and RF tag.

Fig. 8 is a flowchart showing an application example of the flow of the read processing of the reader/writer.

[ description of symbols ]

10: reader-writer

11: upper communication control unit

20: RF communication control unit

21: RF tag determination unit

22: memory processing unit

30: storage unit

40 (40A, 40B, 40C): RF tag

50: PLC (Upper machine)

100: tray for holding food

101: workpiece

120: control unit

130: amplifier unit

S1 to S11, S21 to S31, S41 to S49: step (a)

Detailed Description

An embodiment of an aspect of the present invention (hereinafter also referred to as "the present embodiment") will be described below with reference to the drawings.

Application example of ≡1

First, an example of a scene to which the present invention is applied will be described with reference to fig. 1 and 2. Fig. 1 is a block diagram showing the essential structure of a reader/writer 10 according to the present embodiment. Fig. 2 is a diagram schematically showing a system environment in which the reader/writer 10 according to the present embodiment is used.

As shown in fig. 2, for example, RF tag 40 may be used at a production site for individual management of articles such as parts and products. The RF tag 40 is used by attaching a predetermined plurality of pieces, in this embodiment, three pieces (RF tags 40A, 40B, and 40C) to one pallet (pallet) 100 on which workpieces 101 such as parts and products are placed.

As shown in fig. 1, the reader/writer 10 includes an antenna 35 for performing wireless communication with each of the plurality of RF tags 40 (40A, 40B, 40C), and performs at least one of reading and writing of data with the plurality of predetermined RF tags 40 (40A, 40B, 40C) located in the communication area with each other via the antenna 35. When at least one of reading and writing data with the predetermined plurality of RF tags 40 is performed, the reader/writer 10 integrates memories included in the predetermined plurality of RF tags 40 and performs memory processing as one virtual memory space.

In this way, since the reader/writer 10 integrates the memories of the respective predetermined RF tags 40 and performs memory processing as one virtual memory space, the memory capacity can be virtually increased even if the memory capacity of the respective RF tags 40 is as small as 2KB, for example. Therefore, even if the amount of information required for individual management of articles such as parts and products increases, it is possible to disperse such information in a predetermined plurality of RF tags 40 and perform at least one of reading and writing.

2 structural example

The configuration of the reader/writer 10 according to the embodiment of the present invention will be described in detail below with reference to fig. 1 to 3. Fig. 1 is a block diagram showing the essential structure of a reader/writer 10. Fig. 2 is a diagram schematically showing a system environment in which the reader/writer 10 is used. Fig. 3 (a) and 3 (b) are block diagrams showing the configuration of a system using the reader/writer 10.

[ Structure of reader/writer 10 ]

As shown in fig. 1, the reader/writer 10 performs at least one of reading and writing of data by wireless communication with the RF tag 40. The reader/writer 10 is used as an input device of the PLC (Programmable Logic Controller) 50 host device.

The reader/writer 10 includes a host communication control unit 11, an RF communication control unit 20, a storage unit 30, and an antenna 35.

The upper communication control unit 11 controls communication with the PLC 50. The upper communication control unit 11 performs wireless communication with the PLC 50 or wired communication via a bus or a network. The upper communication control unit 11 can exchange data with the PLC 50 at a high speed of several microseconds to several milliseconds per byte.

The reader/writer 10 communicates with the PLC 50 under control of the upper communication control unit 11, and receives a command from the PLC 50 via the upper communication control unit 11 to perform at least one of reading and writing of data with the RF tag 40.

The antenna 35 performs wireless communication with a predetermined plurality of RF tags 40. The antenna 35 transmits electromagnetic waves including command signals to the predetermined plurality of RF tags 40 based on the control of the RF communication control unit 20, and receives response signals from the predetermined plurality of RF tags 40 to the command.

The RF communication control unit 20 performs at least one of reading and writing of data with a predetermined plurality of RF tags 40 via the antenna 35. The RF communication control unit 20 may be an arithmetic device having a function of comprehensively controlling each unit of the reader/writer 10. The RF communication control unit 20 may control each unit of the reader/writer 10 by executing a program stored in one or more memories (for example, a random access Memory (Random Access Memory, RAM) or a Read Only Memory (ROM)) by one or more processors (for example, a central processing unit (Central Processing Unit, CPU) or the like).

The RF communication control unit 20 interprets the instruction received from the PLC 50 by using the function of the upper communication control unit 11. The commands received from the PLC 50 include a write command for designating writing of data to the RF tag 40 and a read command for designating reading of data from the RF tag 40. The write command and the read command include data related to the data exchange size between the PLC 50 and the reader/writer 10.

The PLC 50 does not need to identify the number of RF tags 40 that the reader/writer 10 communicates to read or write data according to one instruction. As will be described in detail later, the RF communication control unit 20 performs a process of reading or writing to the memory of each of the predetermined plurality of RF tags 40 according to the volume of data to be read or written.

The RF communication control unit 20 converts data included in the write command received from the PLC 50 into data that can be written to the RF tag 40. The RF communication control unit 20 converts, for example, data such as an octal code, a hexadecimal code, and a sixty-four code included in a write command received from the PLC 50 into data of an american standard code for information interchange (American Standard Code for Information Interchange code, ASCII code).

The RF communication control unit 20 converts data read from the RF tag 40 into data that can be transferred to the PLC 50 in response to a read command received from the PLC 50. The RF communication control unit 20 converts digital serial data read out from the RF tag 40 into data such as an octal code, a hexadecimal code, and a sixty-four code.

The RF communication control unit 20 transmits command signals to a predetermined plurality of RF tags 40 and receives response signals via the antenna 35. The RF communication control unit 20 may be configured to perform decoding processing of the response signal received from the RF tag 40. In addition, the wireless communication with the RF tag 40 via the antenna 35 is communication at a speed of several milliseconds to several tens of milliseconds per one byte.

As shown in fig. 3 (a), the reader/writer 10 may also include a plurality of units each separately. For example, the reader/writer 10 may have a configuration in which the control unit 120 including a part of the functions of the upper communication control unit 11 and the RF communication control unit 20, the amplifier unit 130 for amplifying signals, and the antenna 35 are separately provided.

As shown in fig. 3 (b), the reader/writer 10 may be configured such that the upper communication control unit 11, the RF communication control unit 20, and the antenna 35 are integrally formed.

As shown in fig. 1, the RF communication control unit 20 includes an RF tag determination unit 21 and a memory processing unit 22.

The RF tag specification unit 21 specifies a predetermined plurality of RF tags as target RF tags. The RF tag identification unit 21 reads out identification information stored in the memory of the RF tag 40 from each of the plurality of communicable RF tags 40 existing in the communicable area of the antenna 35 via the antenna 35. The RF tag determination section 21 performs the following anti-collision (anti-collision) process: the communicable RF tags 40A, 40B, 40C corresponding to the read identification information are identified as the target RF tags 40A, 40B, 40C.

The identification information of the RF tag 40 includes, in addition to information for identifying the individual of each RF tag 40, identification information of other RF tags 40 included in a predetermined set of a plurality of RF tags 40 holding individual information of one workpiece 101 (see fig. 1). In the anti-collision process, the RF tag determination unit 21 refers to the identification information of each of the plurality of communicable RF tags 40, and determines a set of the plurality of RF tags 40 holding the individual information of one work 101 (refer to fig. 1), thereby determining the target RF tags 40A, 40B, 40C.

The RF communication control unit 20 causes the storage unit 30 to store the identification information read from each of the target RF tags 40A, 40B, and 40C by the RF communication control unit 20 via the antenna 35. The RF tag determination unit 21 manages the identification information of the target RF tags 40A, 40B, 40C stored in the storage unit 30 as an index, thereby setting the addresses of the memories included in the respective target RF tags 40A, 40B, 40C in the virtual memory space. The RF tag determination unit 21 manages, for example, identification information as an index, and sets addresses with respect to the memory blocks of the target RF tags 40A, 40B, and 40C as the first, second, and third virtual memory spaces in the order in which the indexes are sorted.

The identification information of the RF tag 40 is, for example, an identification number set individually for each RF tag 40. The identification numbers are combinations of english alphabets and numerals, and the RF tag identification unit 21 determines the order of reading or writing data by sorting the identification numbers in at least any one of the english alphabets and the numeral orders.

In this way, when at least any one of reading and writing of data from and to the memories included in the plurality of target RF tags 40A, 40B, and 40C is performed, the reader/writer 10 determines in advance the reading order when detecting the plurality of target RF tags 40A, 40B, and 40C in order to sort the identification numbers as an index. Thus, the reader/writer 10 does not need to perform the following processing: information on the order of reading the plurality of target RF tags 40 or the order of writing the plurality of target RF tags 40 is recorded in advance, for example, in correspondence with the identification numbers of the respective RF tags 40. Therefore, the reader/writer 10 can efficiently integrate data read from or written to the plurality of target RF tags 40A, 40B, 40C.

The PLC 50 may be configured to recognize the number of RF tags to be subjected to a command for reading or writing data from/to the reader/writer 10. At this time, the PLC 50 transmits a command for reading or writing data including information on the number of RF tags to be read to the reader/writer 10. The RF tag determination unit 21 acquires the number information indicating the number of RF tags to be received from the PLC 50 via the upper communication control unit 11. The RF tag specifying unit 21 may specify the communicable RF tags 40 as the target RF tags 40A, 40B, and 40C when the acquired number information matches the number of communicable RF tags 40 existing in the communicable area.

The PLC 50 may be an RF tag that can transmit an instruction including identification information for identifying an instruction to read or write data to or from the reader/writer 10. The RF tag determination unit 21 may perform anti-collision processing based on the identification information for identifying the RF tag to be identified received from the PLC 50 via the upper communication control unit 11 and the identification information read from each of the communicable RF tags 40.

The memory processing unit 22 integrates memories included in the target RF tags 40A, 40B, and 40C determined by the RF tag determining unit 21, respectively, as one virtual memory space. For example, when each of the target RF tags 40A, 40B, and 40C has a memory capacity of 2KB, the memory processing unit 22 integrates these memories, and performs memory processing of at least one of reading and writing as one virtual memory space virtually having a memory capacity of 6 KB.

Thus, the user can store information of the capacity which cannot be stored in the memory of one RF tag 40 completely in one virtual memory space formed by integrating the memories of a plurality of RF tags 40 by using a plurality of RF tags 40 which are usually finished products having a small memory capacity. Therefore, since an expensive RF tag having a large memory capacity is not required, an increase in cost can be suppressed, and the capacity of information that can be managed by the RF tag 40 can be increased.

The RF tag specifying unit 21 may calculate the total memory capacity of the communicable RF tags 40 existing in the communicable area, and specify the communicable RF tags 40 as the target RF tags 40A, 40B, and 40C when the amount of data required for the memory processing by the memory processing unit 22 is equal to or less than the total memory capacity. The identification information of the plurality of RF tags 40 that can communicate with the reader/writer 10 and the memory capacity of each RF tag 40 may be stored in the storage unit 30 in advance. The RF tag specifying unit 21 calculates the total memory capacity of the communicable RF tag 40 by calculating the total memory capacity of the RF tag 40 corresponding to the identification information stored in the storage unit 30 based on the identification information read from the plurality of communicable RF tags 40.

Fig. 4 is a diagram showing an example of the flow of data between the reader/writer 10 and the target RF tags 40A, 40B, 40C. Fig. 4 shows a flow of data when the reader/writer 10 reads out 4000 bytes of data from the reference numeral 1000 in the 6KB virtual memory space from the target RF tags 40A, 40B, and 40C, in response to an instruction from the PLC 50.

First, the RF communication control unit 20 of the reader/writer 10 reads out identification information stored in the memory of the RF tag 40 from each of the plurality of communicable RF tags 40 existing in the communicable area of the antenna 35 via the antenna 35 by the function of the RF tag specifying unit 21. The RF tag specifying unit 21 refers to the identification information read from each of the communicable RF tags 40, performs anti-collision processing, and specifies the target RF tags 40A, 40B, and 40C. The RF tag specification unit 21 sets addresses in the virtual memory space for the memories of the specified target RF tags 40A, 40B, and 40C, respectively.

The RF communication control unit 20 first transmits a read command, which requires 1000 bytes of data to be read from the number 1000 of the memory, to the first RF tag 40A by using the function of the memory processing unit 22. The memory processing section 22 acquires 1000 bytes of data transferred from the RF tag 40A as a response to the transmitted read command.

Next, the memory processing section 22 transmits a read command requesting 2000 bytes of data read from the 0000 of the memory to the second RF tag 40B. The memory processing unit 22 acquires 2000 bytes of data transferred from the RF tag 40B as a response to the transmitted read command.

Next, the memory processing section 22 transmits a read command requesting 1000 bytes of data to be read from the 0000 of the memory to the third RF tag 40C. The memory processing section 22 acquires 1000 bytes of data transferred from the RF tag 40C as a response to the transmitted read command.

In addition, although the example shown in fig. 4 shows the reading of data, when writing data to a predetermined plurality of target RF tags 40 by wireless communication, the memory processing unit 22 may similarly integrate memories included in the target RF tags and write the integrated memories as one virtual memory space. The reader/writer 10 can write data to the target RF tags 40A, 40B, and 40C in a flow reverse to the data reading process, for example, in accordance with an instruction from the PLC 50 to write 4000 bytes of data from the 1000 th virtual memory space of 6 KB.

When writing data with a predetermined plurality of target RF tags 40, the RF communication control unit 20 determines the target RF tags 40A, 40B, and 40C by the function of the RF tag determination unit 21, and sets addresses in the virtual memory space for the memories of the determined target RF tags 40A, 40B, and 40C, respectively.

The RF communication control unit 20 first transmits a write command for writing 1000 bytes of data from the number 1000 of the memory to the RF tag 40A to be processed by the memory processing unit 22, and writes 1000 bytes of data to the RF tag 40A.

Next, the memory processing unit 22 transmits a write command for writing 2000 bytes of data from the 0000 of the memory to the RF tag 40B to be processed, and writes 2000 bytes of data to the RF tag 40B.

Next, the memory processing unit 22 transmits a write command for writing 1000 bytes of data from the 0000 of the memory to the RF tag 40C to be processed, and writes 1000 bytes of data to the RF tag 40C.

In this way, the reader/writer 10 can integrate memories included in each of the plurality of target RF tags 40 as one virtual memory space, thereby increasing the capacity of information that can be managed by the RF tag 40.

[ concrete example 1 of the flow of data reading processing of the reader/writer 10 ]

Fig. 5 is a flowchart showing a specific example 1 of the flow of the data reading process of the reader/writer 10.

When the RF communication control unit 20 of the reader/writer 10 acquires a command for reading data received from the PLC 50 via the upper communication control unit 11, the function of the RF tag determination unit 21 is used to execute the anti-collision process (step S1).

The RF communication control unit 20 determines whether or not the collision avoidance process has ended normally (step S2). When the RF tag specifying unit 21 can specify the predetermined plurality of target RF tags 40A, 40B, and 40C, the RF communication control unit 20 determines that the anti-collision process has ended normally (YES in step S2), and proceeds to step S3. When the RF tag specifying unit 21 cannot specify the predetermined plurality of target RF tags 40A, 40B, and 40C, the RF communication control unit 20 determines that the anti-collision process has not ended normally (NO in step S2), and transmits an abnormal end of the process for the command to the PLC 50.

The RF communication control unit 20 performs a read memory process by using the function of the memory processing unit 22, using the addresses in the virtual memory space of the memories included in the target RF tags 40A, 40B, and 40C set by the RF tag determination unit 21. The memory processing unit 22 first transmits a read command to the RF tag 40A of the first processing object among the RF tags 40A, 40B, and 40C of the objects (step S3).

The RF communication control unit 20 determines whether or not the read command can be normally transferred to the RF tag 40A of the first processing target by wireless communication (step S4). For example, when the RF tag 40A of the subject deviates from the communicable area of the antenna 35, the read command cannot be delivered, and it is determined as an abnormality. When the RF communication control unit 20 determines that the read command can be normally delivered to the RF tag 40A (YES in step S4), it proceeds to step S5. When the RF communication control unit 20 determines that the read command cannot be normally delivered to the RF tag 40A (NO in step S4), it transmits an abnormal end of the processing for the command to the PLC 50.

The RF communication control unit 20 reads out data from the RF tag 40A of the first processing target by using the function of the memory processing unit 22 (step S5). In the case where the instruction to read out the data received from the PLC 50 is an instruction to read out 4000 bytes of data from the number 1000 of the virtual memory space of 6KB, the memory processing section 22 receives 1000 bytes of data from the number 1000 of the RF tag 40A as a response.

The memory processing unit 22 then transmits a read command to the RF tag 40B of the second processing object among the RF tags 40A, 40B, and 40C of the objects (step S6).

The RF communication control unit 20 determines whether or not a read command can be normally transferred to the RF tag 40B to be processed by wireless communication (step S7). For example, when the RF tag 40B of the subject deviates from the communicable area of the antenna 35, the read command cannot be delivered, and it is determined as an abnormality. When the RF communication control unit 20 determines that the read command can be normally delivered to the RF tag 40B (YES in step S7), it proceeds to step S8. When the RF communication control unit 20 determines that the read command cannot be normally delivered to the RF tag 40B (NO in step S7), it transmits an abnormal end of the processing for the command to the PLC 50.

The RF communication control unit 20 reads out data from the RF tag 40B of the second processing target by using the function of the memory processing unit 22 (step S8). In the case where the instruction to read out the data received from the PLC 50 is an instruction to read out 4000 bytes of data from the 1000 th order of the virtual memory space of 6KB, the memory processing section 22 receives 2000 bytes of data from the 0000 th order of the RF tag 40B as a response.

The memory processing unit 22 then transmits a read command to the RF tag 40C of the third processing object among the RF tags 40A, 40B, and 40C of the objects (step S9).

The RF communication control unit 20 determines whether or not a read command can be normally transferred to the RF tag 40C to be processed by wireless communication (step S10). For example, when the RF tag 40C to be subjected to the reading command is out of the communicable area of the antenna 35, it is impossible to transfer the reading command, and it is determined that the reading command is abnormal. When the RF communication control unit 20 determines that the read command can be normally delivered to the RF tag 40C (YES in step S10), it proceeds to step S11. When the RF communication control unit 20 determines that the read command cannot be normally delivered to the RF tag 40C (NO in step S10), it transmits an abnormal end of the processing for the command to the PLC 50.

The RF communication control unit 20 reads out data from the RF tag 40C to be processed of the third processing object by using the function of the memory processing unit 22 (step S11). When the instruction read from the data received from the PLC 50 is an instruction to read 4000 bytes of data from the 1000 th order of the virtual memory space of 6KB, the memory processing unit 22 receives 1000 bytes of data from the 0000 th order of the RF tag 40C and transmits the normal end of the processing for the instruction to the PLC 50 in response thereto.

The RF communication control unit 20 integrates 4000-byte data received from the target RF tags 40A, 40B, and 40C by the function of the memory processing unit 22, and transmits the integrated data to the PLC 50.

In this way, the memory processing unit 22 sequentially performs memory processing on all the object RF tags 40A, 40B, and 40C when all the object RF tags 40A, 40B, and 40C are present in the communicable area of the antenna 35 at the time point of performing memory processing and when all the object RF tags 40A, 40B, and 40C are determined by the RF tag determining unit 21.

[ concrete example 2 of the flow of data reading processing of the reader/writer 10 ]

Fig. 6 is a flowchart showing a specific example 2 of the flow of the data reading process performed by the reader/writer 10. As shown in fig. 6, when the RF communication control unit 20 of the reader/writer 10 acquires a command for reading data received from the PLC 50 via the upper communication control unit 11, the function of the RF tag determination unit 21 is used to perform anti-collision processing and confirm the target RF tag set (step S21).

The RF tag identification unit 21 may read out identification information of each of a plurality of target RF tags included in one set written in a memory of at least any one of the plurality of target RF tags existing in the communicable area of the antenna 35, and confirm the target RF tag set. For example, the identification information of the RF tag 40B and the identification information of the RF tag 40C are written in advance in the memory of the RF tag 40A together with the identification information of the RF tag 40A. The RF tag determination unit 21 may confirm that the target RF tag set includes the RF tags 40A, 40B, and 40C based on the identification information of the RF tags 40A, 40B, and 40C read from the memory of the RF tag 40A.

In addition, information indicating the reading order of each of the plurality of target RF tags may be recorded in the memory of at least one of the plurality of target RF tags together with the identification information of each of the plurality of target RF tags included in one set. At this time, the process of sorting the identification numbers as the index described above may be omitted.

The RF tag determination unit 21 may confirm that the target RF tag set includes the RF tags 40A, 40B, and 40C based on information of the target RF tag set included in the instruction read out from the data received from the PLC 50. At this time, the instruction from the PLC 50 includes information of the RF tags 40A, 40B, and 40C in the RF tag set including the read target of the data. For example, the instruction from the PLC 50 may include identification information of each of the RF tags 40A, 40B, and 40C constituting the RF tag set.

The instruction for reading the data received from the PLC 50 may include information indicating the order of reading the RF tags to be read. At this time, the process of sorting the identification numbers as the index described above may be omitted.

The RF communication control unit 20 performs the processing of steps S22 to S31 after performing the anti-collision processing and the confirmation of the target RF tag set in step S21 by using the function of the RF tag determination unit 21. The processing of step S22 to step S31 is the same as the processing of step S2 to step S11 described above, and therefore, the description thereof will be omitted.

[ application example of data read-out processing of reader-writer 10 ]

In addition, at the time point when the memory processing is performed by the memory processing unit 22, not all the target RF tags 40a and the RF tag 40B, RF tag 40C may exist in the communicable area of the antenna 35. At this time, the memory processing unit 22 may sequentially perform memory processing for the RF tags to be located in the communicable area of the antenna 35, and sequentially perform memory processing for the remaining RF tags to be located at the time points of entering the communicable area of the antenna 35. Consider, for example, the following: in a production line in which the tray 100 with the RF tag 40 mounted thereon is conveyed by a conveyor, the RF tag 40 gradually and sequentially enters the communicable area of the antenna 35 due to the conveying movement of the tray 100.

Fig. 7 is a diagram showing the flow of data among the PLC 50, the reader/writer 10, and the RF tags 40A, 40B, and 40C in the case where not all the target RF tags 40A, 40B, and 40C are present in the communicable area of the antenna 35.

As shown in fig. 7, the RF communication control unit 20 of the reader/writer 10 acquires a read instruction received from the PLC 50 via the upper communication control unit 11. The RF communication control unit 20 determines a predetermined plurality of target RF tags 40 by using the function of the RF tag determination unit 21. The RF tag specification unit 21 may specify the plurality of target RF tags 40 with reference to the content of the instruction from the PLC 50.

The RF tag identification unit 21 may also identify a plurality of target RF tags 40 by referring to identification information read from the RF tags 40A existing in the communicable area of the antenna 35. The RF tag specifying unit 21 refers to the identification information of a predetermined plurality of target RF tags 40 included in the identification information read from the RF tags 40 existing in the communicable area of the antenna 35, and specifies the target RF tags 40A, 40B, and 40C.

When the RF tag 40 is not present in the communicable area of the antenna 35, the RF tag determination unit 21 may wait until the RF tag 40 reaches the communicable area of the antenna 35, confirm that the RF tag 40 reaches the communicable area of the antenna 35, and then read out the identification information from the RF tag 40.

The memory processing unit 22 has a function of confirming whether or not each of the predetermined plurality of target RF tags 40A, 40B, 40C determined by the RF tag determining unit 21 is present in the communicable area of the antenna 35. The memory processing unit 22 has the following functions: when the predetermined plurality of target RF tags 40A, 40B, and 40C determined by the RF tag determining unit 21 are not present in the communicable area of the antenna 35, it is checked whether or not the target RF tags have arrived in the communicable area of the antenna 35. The memory processing unit 22 sequentially executes data reading processing from the target RF tag 40 existing or reaching the communicable area of the antenna 35.

For example, the memory processing unit 22 acquires a read instruction from the PLC 50 to identify the target RF tag 40A, 40B, 40C, and then reads data from the target RF tag 40A existing in the communicable area of the antenna 35. When the read instruction acquired from the PLC 50 is an instruction to read 4000 bytes from the memory No. 1000, the memory processing unit 22 first reads 1000 bytes of data from the memory No. 1000 of the target RF tag 40A.

The memory processing unit 22 then confirms that the target RF tag 40B has reached the communicable area of the antenna 35, and reads out 2000 bytes of data from the 0000 number of the memory of the target RF tag 40B. Then, the memory processing unit 22 confirms that the target RF tag 40C has reached the communicable area of the antenna 35, and reads 1000 bytes of data from the 0000 number of the memory of the target RF tag 40C.

In this way, the reader/writer 10 can sequentially read data from the plurality of target RF tags 40 by expanding the read range of the target RF tags 40 outside the communicable area of the antenna 35. Thus, the memories included in the RF tags 40 can be integrated to serve as one virtual memory space, thereby increasing the capacity of information that can be managed by the RF tag 40.

In addition, when writing data to a predetermined plurality of target RF tags 40 by wireless communication, the memory processing unit 22 may similarly integrate memories included in the target RF tags, and write data to the plurality of target RF tags 40 as one virtual memory space. The reader/writer 10 can write data to the target RF tags 40A, 40B, and 40C in a flow reverse to the data reading process according to an instruction from the PLC 50. That is, the memory processing unit 22 can confirm that the target RF tag 40 has arrived in the communicable area of the antenna 35, and write data of a predetermined capacity in a predetermined position of the memory of the target RF tag 40.

[ flow of processing performed by the memory processing section 22 ]

Fig. 8 is a flowchart showing an example of the flow of the data reading process performed by the memory processing unit 22 when not all the target RF tags 40A, 40B, 40C are present in the communicable area of the antenna 35.

The RF communication control unit 20 waits for the first one of the target RF tags 40A, 40B, 40C, which is determined by the function of the RF tag determining unit 21, to reach the communicable area of the antenna 35, and reads out data of a predetermined capacity from a predetermined position of the memory of the target RF tag 40A by the function of the memory processing unit 22 (step S41).

The RF communication control unit 20 determines whether or not the memory processing unit 22 can normally read data from the target RF tag 40A (step S42). If the RF communication control unit 20 determines that the memory processing unit 22 can read data from the target RF tag 40A normally (YES in step S42), it proceeds to step S43. When the RF communication control unit 20 determines that the memory processing unit 22 cannot read data from the target RF tag 40A normally (NO in step S42), it notifies the PLC 50 of abnormal end of data reading, and ends the process.

The RF communication control unit 20 notifies the PLC of the response received from the target RF tag 40A (step S43).

The RF communication control unit 20 waits for the second target RF tag 40B for reading data to reach the communicable area of the antenna 35, and reads data of a predetermined capacity from a predetermined position of the memory of the target RF tag 40B by the function of the memory processing unit 22 (step S44).

The RF communication control unit 20 determines whether or not the memory processing unit 22 can normally read data from the target RF tag 40B (step S45). If the RF communication control unit 20 determines that the memory processing unit 22 can read data from the target RF tag 40B normally (YES in step S45), it proceeds to step S46. When the RF communication control unit 20 determines that the memory processing unit 22 cannot read data from the target RF tag 40B normally (NO in step S45), it notifies the PLC 50 of abnormal end of data reading, and ends the process.

The RF communication control unit 20 notifies the PLC of the response received from the target RF tag 40B (step S46).

The RF communication control unit 20 waits for the third target RF tag 40C to read data to reach the communicable area of the antenna 35, and reads data of a predetermined capacity from a predetermined position of the memory of the target RF tag 40C by the function of the memory processing unit 22 (step S47).

The RF communication control unit 20 determines whether or not the memory processing unit 22 can normally read data from the target RF tag 40C (step S48). If the RF communication control unit 20 determines that the memory processing unit 22 can read data from the target RF tag 40C normally (YES in step S48), it proceeds to step S49. When the RF communication control unit 20 determines that the memory processing unit 22 cannot read data from the target RF tag 40C normally (NO in step S48), it notifies the PLC 50 of abnormal end of data reading, and ends the process.

The RF communication control unit 20 notifies the PLC of the reception of the response from the target RF tag 40C, integrates the data read from each of the target RF tags 40A, 40B, and 40C, and transmits all the data to the PLC 50 (step S49), thereby notifying the PLC 50 of the normal end of the processing for the instruction, and ending the processing.

[ implementation by software ]

The control blocks (particularly, the upper communication control unit 11 and the RF communication control unit 20) of the reader/writer 10 may be realized by logic circuits (hardware) formed on an integrated circuit (IC chip) or the like, or may be realized by software.

In the latter case, the reader/writer 10 includes a computer that executes commands of a program as software for realizing the respective functions. The computer includes, for example, one or more processors, and includes a computer-readable recording medium storing the program. In the computer, the processor reads the program from the recording medium and executes the program, thereby achieving the object of the present invention. As the processor, for example, a CPU may be used. As the recording medium, a tape, an optical disk, a card, a semiconductor memory, a programmable logic circuit, or the like may be used in addition to a "non-transitory tangible medium", such as a ROM, or the like. Further, a RAM or the like for expanding the program may be also included. Further, the program may be provided to the computer via any transmission medium (communication network, broadcast wave, or the like) that can transmit the program. In addition, an embodiment of the present invention may be realized by a form of a data signal embedded in a carrier wave, which is realized by electronically transmitting the program.

[ summary ]

The reader/writer according to an embodiment of the present invention is configured to perform at least one of reading and writing of data by wireless communication with an RF tag, and includes: an RF tag specifying unit that specifies a predetermined plurality of RF tags as target RF tags; and a memory processing unit that integrates memories included in each of the plurality of target RF tags, and performs memory processing of at least one of reading and writing as one virtual memory space.

According to the above configuration, the memories included in the plurality of target RF tags can be integrated, and at least one of the memory processing for reading and writing can be performed as one virtual memory space. Thus, a plurality of RF tags having a small memory capacity, which are usually manufactured, can be used, and thus necessary information of the memory capacity which cannot be completely stored in one RF tag can be stored in one virtual memory space. Therefore, the cost of the RF tag can be suppressed from increasing, and the capacity of information that can be managed by the RF tag can be increased.

In the reader/writer according to an embodiment of the present invention, the RF tag determination unit may be configured to set an address of a memory included in each of the target RF tags in the virtual memory space by managing identification information of the target RF tag as an index.

According to the above configuration, when at least one of reading and writing of data from and to the memories included in the plurality of target RF tags is performed, the reading order at the time of detecting the plurality of target RF tags can be determined in advance as an order corresponding to the identification number managed as the index. Thus, the following process need not be additionally performed: information on the order of reading out or writing a plurality of target RF tags is recorded in advance. Therefore, data integration can be performed efficiently. Therefore, even if a plurality of memories of the RF tag for objects are used as one virtual memory space, the data processing can be made efficient, and the data capacity can be increased.

In the reader/writer according to an embodiment of the present invention, the RF tag identification unit may receive, from an external host device, number information indicating the number of the RF tags to be communicated, and identify the RF tags to be communicated as the RF tags to be communicated when the number information matches the number of the RF tags to be communicated existing in the communication area.

According to the above configuration, the reader/writer can appropriately determine the number of communicable RF tags corresponding to the instruction from the host machine as the target RF tag.

In the reader/writer according to an embodiment of the present invention, the RF tag specifying unit may calculate a total memory capacity of the communicable RF tag existing in the communicable area, and may specify the communicable RF tag as the target RF tag when an amount of data required for the memory processing is equal to or smaller than the total memory capacity.

According to the above configuration, the reader/writer can read and write data after confirming that the total memory capacity of the plurality of target RF tags reaches the capacity required for memory processing. Thus, when a plurality of memories of the target RF tag are used as one virtual memory space, the capacity required for reading or writing data does not become insufficient in the middle of the memory processing and ends abnormally. Therefore, the reader/writer can efficiently perform processing of at least any one of reading and writing of data to the plurality of target RF tags.

In the reader/writer according to an embodiment of the present invention, the RF tag specifying unit may read out identification information from among the communicable RF tags stored with identification information of a plurality of the target RF tags, the communicable RF tags being present in the communicable area, and specify the communicable RF tag corresponding to the read out identification information as the target RF tag.

According to the above configuration, a plurality of object RF tags can be identified by referring to the identification information read from the communicable RF tags, and the identification of the object RF tags can be performed efficiently.

In the reader/writer according to an embodiment of the present invention, the memory processing unit may sequentially perform memory processing on all the object RF tags when all the object RF tags are present in the communicable area at a time point of performing the memory processing, and sequentially perform memory processing on the object RF tags present in the communicable area when not all the object RF tags are present in the communicable area at a time point of performing the memory processing, and sequentially perform memory processing on the remaining object RF tags when the remaining object RF tags are present in the communicable area.

According to the above configuration, the determinable region of the plurality of target RF tags can be enlarged outside the communicable region, and the memory of the plurality of RF tags that do not enter the communicable region can be used as one virtual memory space, thereby performing at least one of reading and writing of data.

According to the above method, the memories included in each of the plurality of target RF tags can be integrated, and at least one of the memory processes of reading and writing can be performed as one virtual memory space. Thus, a plurality of RF tags having a small memory capacity, which are usually manufactured, can be used, and thus necessary information of the memory capacity which cannot be completely stored in one RF tag can be stored in one virtual memory space. Therefore, the cost of the RF tag can be suppressed from increasing, and the capacity of information that can be managed by the RF tag can be increased.

In order to solve the above-described problem, a program according to an embodiment of the present invention causes a computer to function as the RF tag identification unit and the memory processing unit while causing the reader/writer to operate.

According to the above configuration, an increase in cost of the RF tag can be suppressed, and the capacity of information that can be managed by the RF tag can be increased.

The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and embodiments in which technical means disclosed in the different embodiments are appropriately combined are also included in the technical scope of the present invention.

Claims

1. A reader/writer which reads and writes data by wireless communication with a radio frequency tag, comprising:

a radio frequency tag determination unit that determines a predetermined plurality of radio frequency tags as target radio frequency tags; and

a memory processing unit that integrates memories included in each of the plurality of target radio frequency tags and performs memory processing of at least one of reading and writing as one virtual memory space, wherein,

the radio frequency tag determination section manages identification information of the object radio frequency tag as an index, thereby setting an address of a memory included in each of the object radio frequency tags in the virtual memory space,

The radio frequency tag determination unit receives, from an external host device, number information indicating the number of radio frequency tags to be targeted, and determines the radio frequency tag to be targeted when the number information matches the number of radio frequency tags to be targeted existing in a communicable area.

2. The reader/writer according to claim 1, characterized in that,

the radio frequency tag determination unit calculates a total memory capacity of a communicable radio frequency tag existing in a communicable area, and determines the communicable radio frequency tag as the target radio frequency tag when an amount of data required for the memory processing is equal to or less than the total memory capacity.

3. The reader/writer according to claim 1, characterized in that,

the radio frequency tag determination section reads out identification information of a plurality of radio frequency tags to be communicated, from among radio frequency tags to be communicated existing in a communicable area, the identification information being recorded therein, and determines the radio frequency tag to be communicable corresponding to the read out identification information as the radio frequency tag to be communicated.

4. A reader/writer according to claim 1 or 3, characterized in that,

The memory processing unit sequentially performs memory processing on all the object radio frequency tags when all the object radio frequency tags exist in a communicable area at a time point of performing the memory processing,

the memory processing unit sequentially performs memory processing on the object radio frequency tags existing in the communicable area when not all the object radio frequency tags exist in the communicable area at a time point of performing the memory processing, and sequentially performs memory processing at a time point when the rest of the object radio frequency tags enter the communicable area.

5. A method for controlling a reader/writer, comprising the steps of:

determining a plurality of specified radio frequency tags as object radio frequency tags; and

the memory processing for integrating memories included in each of the plurality of target radio frequency tags and performing at least one of reading and writing as one virtual memory space, wherein,

the step of determining the prescribed plurality of radio frequency tags as object radio frequency tags includes:

managing the identification information of the object radio frequency tag as an index, thereby setting the address of the memory included in each object radio frequency tag in the virtual memory space,

And receiving number information representing the number of the object radio frequency tags from an external upper machine, and determining the communicable radio frequency tags as the object radio frequency tags when the number information is consistent with the number of the communicable radio frequency tags existing in the communicable area.

6. A storage medium storing a program that causes the reader/writer control method according to claim 5 to operate, and the program is executed to implement the control method according to claim 5.